utility knife handle

[dbotos 5]

I need to work on my print quality, but just wanted to share something functional I designed and printed. It's a two-piece handle for a utility knife blade. I modeled one half, mirrored it, and then enlarged the holes in the second half and added countersinks to those holes (the holes are sized for 4-40 screw tap and clearance). In hindsight, I should have made the halves unequal thickness and just put the recess for the blade in one half. I guess I will have to try version 2 tomorrow. I did test this one on a cardboard box and it cut nicely (especially since it has a brand new blade). After printing, I had to drill out the holes larger, tap the holes in the one side, and touch up the countersinks, but all in all, I'm pretty happy since I have just gotten my printer running this week.

[dbotos 5]

Here's version 2.0. I printed much slower (50 mm/s) and used 100% fill density. I had to snug the extruder pinch knob a couple times to get it feeding consistently. Print temperature was 220*C.

The holes in the halves didn't quite line up perfectly, so they're shifted slightly when screwed together (I think I will just model holes in one half and then drill through into the other half after printing). I also accidentally peeled a few strands from the perimeter while sanding it with some 400 grit sandpaper. The blade recess needs to be a smidge larger too. I think I will also increase the wall thickness setting.

[owen 19]

That looks pretty good. Are you going to put it on Thingiverse?

[dbotos 5]

Thanks. I will definitely post some form of it up there. I'm up to version 5 now...

I did one last version of the two-piece before I decided to try a one-piece (with the part being built on edge instead of on its side). The first one-piece didn't turn out so great cause it wasn't very stable (only 1/4" wide) and it partially broke loose from the platform as it was printing the upper portion. I solved that problem by adding some removable stabilizers underneath it for version 5. Version 5 was supposed to have the little nub on the underside too, but the first layer of the nub didn't adhere well to the platform (since it was basically a single line) and it got hosed from there (I might change it to being a "bite" shape out of the perimeter instead). Also came up with a cap that makes it look like a jumbo USB key or a cigar cutter (also a one-piece). Still need to work on tuning some parameters to get better print quality, but I've just been having too much fun messing around with different designs.

If anyone wants to make some knives until I get something uploaded to Thingiverse, you really only need the blade recess dimensions and then the rest of the handle can be built around that:

-recess thickness = 0.025" (blade measured 0.023")

-recess height = 0.770" (was .750" in drawing above)

-distance from breakout at top to rear blade hole = .775"

-distance between blade holes (center to center) = .260"

-distance from rear blade hole center to closest corner = .520" (was .500" in drawing above)

-distance from top edge of recess to blade hole centers = .100" (was .063" in drawing above)

I used 4-40 screws, but M3s should work as well since they are just a tiny bit larger.

[ian 32]

fantastic.

really nice practical and quick use of the ultimaker.

we need to see more people doing this kind of thing.

building a ultimaker workshop,.... tool by tool.

Ian

[mrjaimejun 0]

that creations of yours are so impressive.

[gaaranet 0]

yeahh!!! IAN were the same ideas it is a easy and quick to use the ultimaker knife-handle